6:00

you get various chirps and weeps there. And

6:03

then one of the famous one is the chirp of the

6:05

first detection of a gravitational wave right back in 2015. That

6:08

was much touted at the press conference

6:10

as the increase in frequency went

6:13

up. And then what NASA have done,

6:15

and the thing that you're thinking about, I think

6:17

is scans of images as well where they kind

6:19

of run across it and they convert the brightness

6:22

and colors into intensity and frequency

6:24

too. So what they're doing when

6:26

people get this and they've instead

6:28

of a sort of visualization, so

6:31

taking the data and seeing it as an image,

6:33

they're taking the kind of color and intensity and

6:35

converting it to sound. And that's what they're doing.

6:38

Or you can also say, take something you hear at

6:40

radio wavelengths and convert that into audio too, just as

6:42

we would with kind of a many, many other things.

6:44

And you might have to adjust the frequency a lot.

6:46

It might be really high pitched or really low pitched

6:49

and you have to bring it into the range

6:51

that humans can hear it. But I think

6:53

it's completely legitimate. It's another way of understanding

6:55

the universe around us. So nothing we were

6:57

about it. We can be completely unabashed about

6:59

watching and listening to these things. And

7:03

the Perseus one that Izzy played, that one

7:05

I think actually technically is sound

7:08

waves. Sound waves

7:10

in like commerce there, because I mean,

7:13

it was sort of like a shockwave that was

7:15

discovered by the Chandra telescope, sort of through the

7:17

hot X-ray gas around this black hole. So technically

7:19

you could turn that shockwave again into a soundwave

7:22

and then pitch it, like you said, Robert. But

7:24

what I love about these things is that, I've got

7:26

so many colleagues that are perhaps visually impaired in some

7:29

way. And I feel like obviously astronomy is this science

7:31

of images, but sonifying data or

7:33

even like these projects that

7:35

3D print images of galaxies

7:37

or other images in the universe so that people

7:39

who are visually impaired can engage with astronomy is

7:41

just amazing. And I think people are so clever

7:44

for the ways that they think up that we

7:46

can do this. It's great. Totally,

7:48

totally agree with that. Okay,

7:50

Becky Laudere has been in touch

7:52

and says, hello, I was listening

7:54

to the recent episode about quakes

7:56

and Dr. Becky's explanation of how

7:58

Earth's moon was. formed got me

8:00

wondering, what holds the material

8:02

that coalesced to form it together? And

8:06

assuming that is how rocky planets and

8:08

moons are formed, what holds them all

8:10

together? I understand gravity is what is

8:12

causing the coalescing of material, but what

8:15

is it that holds the material together

8:17

as well? I hope everything's well with

8:19

you all. Cheers. Thanks,

8:21

Loda. I mean, it's still gravity holding everything

8:23

together. Yes, okay, everything comes in and coalesces

8:25

under gravity, but then once it's there, it's

8:28

held together with gravity as well, especially as

8:30

objects get bigger and bigger, gravity gets stronger,

8:32

it can start to round things as well.

8:34

So, you know, they start looking like

8:36

lumpy potatoes and start looking like planets

8:38

and moons. So

8:40

yeah, I mean, that sounds like a boring answer,

8:42

Loda, but I think it's just gravity. Unless, I

8:45

guess you're asking about what physical

8:47

forces then hold atoms together,

8:49

in which case on those scales, you're

8:51

talking about the strong force, which is

8:53

another one of the four fundamental forces

8:56

in physics that holds together like neutrons

8:58

and protons, like in the nucleus of

9:00

an atom. So I guess it's a

9:02

little bit of both of those things. And then of course,

9:04

any other forces you have to like hold together molecules and

9:06

things like this, like, you know, like ionic bonding and

9:08

covalent bonding, but then I feel like we should ask

9:10

a chemist. We

9:14

don't have one of those on the team. No,

9:16

no. None of us is either an astro

9:18

chemist either. But

9:21

you know, speaking of lumpy potatoes, I always laugh

9:23

if you look at the actual size of

9:27

it is not this perfect sphere. And

9:29

you know, most

9:31

planets are kind of most rocky planets

9:33

are a bit lumpy potato s.

9:36

There's basically no perfect spheres in astronomy

9:38

pretty much except, I mean, you know,

9:40

yeah, I'm just thinking black holes, you

9:42

know, nothing, nothing is perfect. Yeah. It's

9:45

all slightly beautifully imperfect and irregular. Yeah,

9:47

I love it. We had a visit at the

9:49

department the other day in Oxford from Professor Adam

9:51

Burrows, who was giving like a lecture. And he's

9:53

really into both like supernova and planets. And I

9:56

we were sort of having coffee with him as

9:58

sort of like the post. stocks do and

10:00

stuff like this. And we were saying

10:02

to him, how did you go from like one

10:04

different field of astronomy of supernova like into studying

10:07

planets? And he went, I just really like spheres

10:09

to be honest. They all just

10:11

really made me laugh. And

10:13

we were all there like, but technically they're not

10:15

really spheres, are they? Actually

10:18

I'm playing spheroid, but I

10:20

think he was, he was just joking that basically I

10:23

think the physics is kind of the same, whether you're

10:25

looking at something that's star sized or planet sized. I

10:27

feel like we're going to get a lot more questions

10:30

about this anyway, maybe go to the

10:32

next one. Robert, can you help with

10:34

this question about aurorae? Besides

10:37

Earth and Jupiter, which other

10:39

planets or moons in our

10:41

solar system experience aurorae? Also

10:43

could JWST detect the presence of

10:46

aurorae on exoplanets and would that

10:48

help us better understand the chemical

10:50

composition of their atmospheres? Yeah,

10:53

that's a really good one. Well,

10:55

at the very least, I mean, we obviously see

10:57

aurorae on Earth because many of us saw those

10:59

a few weeks ago. Many of us, not me.

11:02

Many of us, I know. I wasn't

11:04

trying to wind up Izzy there, I

11:06

promise. You know, your time will

11:09

come again, Izzy, I promise. But at the

11:11

very least, we see them on actually loads

11:13

of places in the solar system. So they're

11:15

seen on Venus and Mars and Jupiter and

11:17

its moon Io and Uranus and Neptune, all

11:19

of those. Now they're seen in different ways.

11:22

The aurorae on Venus, they're sort of fairly

11:24

faint flashes. And on Mars, they're associated, because

11:26

Mars doesn't have a global magnetic field like

11:28

the Earth. It had one once and what

11:31

you've got left are magnetized rocks. And where

11:33

those rocks are strongly magnetized, you get localized

11:35

aurorae. So they appear over the whole planet.

11:38

And then you've also got

11:40

Jupiter and Saturn and the gas giants and

11:42

the ice giants, Uranus and Neptune. They have

11:44

really big displays. The ones on Jupiter and

11:46

Saturn are quite bright and they think they're

11:48

prominent ultraviolet. So they've been seen by the

11:51

Hubble Space Telescope. And now there are JWST

11:53

images of at least the ones around Jupiter. And they're

11:55

now going to look at Saturn and Uranus and

11:57

Neptune too. And those are a bit fainter.

12:00

but they give out radio emission as well,

12:02

so we know they're there. So they're really

12:04

widespread through the solar system, wherever the sun's

12:06

influence is, essentially, and it's sending this stream

12:08

of particles towards a planet, then you expect

12:10

that kind of interaction. And as

12:12

for exoplanets, yes, that does happen too. And

12:15

there's a good recent example, which is

12:17

using a telescope called LOFA, or low-frequency

12:19

radio telescope, and it's got these antennae

12:21

distributed across Europe. And, you know, the

12:24

very sensitive things that were kind of flat on

12:26

the ground, but they work as a big radio

12:28

telescope. And that found a Rory associated with a planet

12:30

26 light years away, fairly

12:32

close by the standards of planets around

12:34

other stars that star GJ1151, which is

12:36

a red dwarf star, so quite a

12:39

small, cool one, much more than the

12:41

sun. And so with sensitive

12:43

radio telescopes, we definitely find the Rory, the

12:45

Nexoplanets, and it's a way of knowing actually

12:47

that there are planets there, and also to

12:49

a certain extent, you're quite right what they're

12:51

made of, how their atmospheres work, how their

12:53

magnetic fields work, and how they interact with

12:55

their stars. So the answer is yes, lots

12:58

of Northern Nights display, and is this time

13:00

will come where routine viewers need to get you

13:02

off to Alaska to do a podcast with you.

13:04

I mean, that would be amazing. I'll

13:06

wait for that, you know, the Christmas

13:08

specials. That sounds good. Yeah. Now,

13:11

specifically with JWST, because that's a telescope and

13:13

observatory that's operating infrared wavelengths, it's going to

13:15

find it a lot harder to see Rory

13:18

around those exoplanets. And that's because they don't

13:20

have a lot of infrared emissions. So in

13:22

our solar system, they know that they're much

13:24

closer, they're brighter, and so on, it's going

13:27

to be a lot easier. By the time

13:29

you go from say, hundreds of

13:31

millions of kilometers to trillions of kilometers to

13:33

the typical distances to even the nearest stars,

13:35

it's going to be a real struggle. So

13:37

we are going to rely on other telescopes

13:39

like Loafar, like radio telescopes, to do that for

13:41

us instead. Lovely. Thanks, everyone. And

13:44

thanks for sending in your questions.

13:46

Do keep them coming. You can

13:48

email podcast at ras.ac.uk. And we're

13:50

also on Instagram at supermassivepods. We'll

13:52

be back next time with a

13:54

Q&A special on Black Holes. Izzy

13:56

has finally given me what I've

13:58

been asking for. asking for. But

14:01

until next time everybody, happy

14:03

stargazing.